| 摘要 |
PURPOSE:To control power automatically with a simple operation by providing timing control means for controlling light quantity in an area excepting the maximum printable area with respect to the horizontal scanning direction at an unblanking time and in an area excepting image assurance areas at front and rear ends in a record medium with respect to the vertical scanning direction. CONSTITUTION:When a light emission quantity is higher than a desired value, a light quantity signal is made to be down by 1 step. When the light emission quantity is lower than the desired value, the light quantity signal is made to be up by 1 step. This process is to be continued until the light emission quantity becomes equal to the desired value. When the light emission quantity became equal to the desired value, an unblanking start data is returned to an original value. Thereafter, a vertical synchronization request signal is outputted so as to process an image formation. Accordingly, the laser beam strikes upon an edge of a polygon mirror during the image formation so that the influence of the scattered light on the image can be avoided. Thereafter, it is determined whether a printout for a next page exists or not. When it exists, an APC is performed. If not, the light emission quantity signal is turned off. |
